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[en] This publication presents the proceedings of the IAEA International Conference on the Management of Spent Fuel from Nuclear Power Reactors, held in 2019, with the theme ‘Learning from the Past, Enabling the Future’ and includes the papers and posters presented at the conference. The purpose of the event was to provide a forum for the exchange of information on national spent fuel management strategies and on the ways in which a changing energy mix could influence these strategies and on how they support the achievement of national energy goals. The broad scope of the conference covered all stages of the management of spent fuel from the past, present and future technologies, and how it can be affected by the decisions taken in the rest of the nuclear fuel cycle. The event brought together experts from countries with decades of nuclear power operating experience and those from countries currently developing or considering a nuclear power programme. The importance of sharing data, operational experience, lessons learned and international collaboration in research and development (R&D) activities, and how its development and implementation can lead to attainable solutions was highlighted. Special attention was given to the young generation of professionals to support bridging the gap with the current ageing industry workforce.
[en] At the Agency, we have noted that there is strong interest in this conference, and that holding it regularly brings several benefits. This conference is the fourth of its kind, with the most recent held in 2015. The conference series allows all involved to regularly review progress made in the safe, secure and sustainable management of spent fuel. Holding the conferences regularly also enable the spent fuel community to keep the momentum and underline the message that the safe, secure and sustainable management of spent fuel is a must – not only because it is the right thing to do, but also because it is the key to the future of nuclear energy. In addition, regular conferences on spent fuel management help the Agency develop and adjust its activities related to this topic.
[en] Nuclear technologies have an important role to play in mitigating greenhouse gas emissions, in monitoring the effects of climate change and in adapting to them. At present, nuclear power produces about 10 percent of the world’s electricity, but it generates almost one third of the global total of low carbon electricity. However, for nuclear power to be sustainable, the safe, secure, reliable and efficient management of its fuel cycle is paramount, in particular the management of the spent fuel and radioactive wastes generated. It is a complex undertaking, involving storage, transportation, recycling and disposal steps. This challenge is as much for policymakers as for engineers. Indeed, technical solutions for the management of spent fuel exist – whether reprocessing and recycling, or conditioning for spent fuel disposal in deep underground repositories. However, the implementation of any of these options can take decades, and allocation of the necessary resources is often challenging.
[en] Many countries have put big emphases on renewables and we do expect to see a large deployment of variable renewable energy in next few decades. I think that’s natural and I think that there’s a lot of benefits of renewables for many countries. The NEA has done a lot of technical analysis and economic analysis on this. Our analysis highlights that we’re not going to see a one size fits all approach that will work for every country around the world. We’re going to see that for some countries with the right kind of resources that it’ll make sense to have higher proportions of renewables, solar or wind, depending on the circumstances. But for others it won’t. Every country really needs to analyse very closely how it’s going to meet its obligations and not assume that just because someone sets an arbitrary target that they can meet that target in an economic fashion. And whatever your resource is, when you reach that 40 to 50% level of variable renewables the ability to control the grid in a reliable fashion comes into challenge. And there’s a lot of experts that tell me, grid experts, that they really don’t know how to manage a grid with higher loads in renewables in that. At least not the large grids that are in most OECD countries. While these big investments in renewables are proceeding, emissions have continued to increase. As a matter of fact, IEA notes that last year we had highest emissions globally of CO2 that we’ve ever had. So, despite the big investment in renewables, despite the political focus on climate change, we aren’t making enough progress. So, I think this does present an opportunity for nuclear energy to reassert itself. There’s a lot of discussion about small reactors, about Gen IV reactors and there’s a lot of energy in a lot of places to push forward those technologies. And we’re going to have to see these technologies be successful if nuclear is going to be more cost effective and flexible, and if nuclear is going to be able to ensure very high levels of safety at low cost. At the same time, we have to deal with the fuel cycle and nuclear waste. And this issue of “how does nuclear fit into the evolving framework” is one in which that we spend a lot of time at the NEA. This is very challenging. You know nuclear energy grew up at a time when there were very high energy prices. It grew up at a time when large institutions, large electric utilities had a lot of leeway, had a lot of resources. And now we’re moving into a period where there’s less money in the electric business, less resources for research and less resources in terms of personnel. So how do we fit in that new framework? One of the big issues obviously is going to be is the issue you’re here to talk about – high level waste. The public expects us to deal with high level waste. The public expects that we should know what to do with the materials that we’re generating in our nuclear power plants. And we have quite a bit it around; we have about 300 000 tonnes that we’ve been regenerating in NEA countries over the last several decades.
[en] Let me start by saying that in Europe we have at the moment 14 member states that use nuclear energy and 14 that don’t. But if I take the lead, from the two previous speakers, we also published a 2050 scenario last November that puts nuclear energy at 15% on average in 2050 as a source of energy in the EU, accompanied by a massive deployment (80–85%) of renewables technology. In such a scenario, the safe and responsible management of radioactive waste is a fundamental element to keep nuclear energy in the energy mix. At the European Commission, we have been consistently working on that for the past ten years, and we have developed a regional safety legal framework that is taken as a reference in the world with spent fuel and radioactive waste management being a key element of this. The directive is still young, it was born in 2011 and implemented in steps in 2013 by becoming national law in the EU Member States and in 2015 by having Member States national programmes to describe how they’re going to put in place their policies for the management of spent fuel and radioactive waste. It is particularly important that roles are clear and that political priorities are transformed into actual projects and actions. The directive is based on a key principle, which is that you cannot transfer burdens the following generations. Therefore, while it’s true that we can safely manage spent fuel and we can temporarily storage it already today. But this is no excuse in order to sit back and wait for something else to happens. One of the key elements of the reporting that was made, and the Radioactive Waste Directive, is the notion of inventories, namely how much radioactive wastes and spent fuel do we have in the EU. So, we have something like 50 000 tonnes of spent fuel generated in the past and Member States estimate that this will rise to 80 000 tonnes by 2030. And if you look at this graph, it shows you that the situation is quite diverse. For low and intermediate waste disposal we have a situation that advances and progresses consistently. Whereas for high level waste and spent fuel, very little is happening. This is the situation that we have to face nowaday.
[en] Several recurring themes emerged over the week. The value of sharing data and operational experience was evident in every session. Your presentations clearly indicated collaborations lead to better solutions, whether they be happening now — like the IAEA Underground Research Laboratories Network for Geological Disposal, the high burnup demonstration cask collaboration, and the efforts of the European Commission on advanced fuel cycles including partitioning and transmutation — or collaborative efforts still in the conceptual phase — such as a multinational repository. The IAEA provides many opportunities for newcomers to learn from mature programmes.
[en] The theme we chose for the week is “Learning from the Past, Enabling the Future.” Each country is on its own journey with nuclear power and has its own past and future. Likewise, each individual is on his or her own journey. Whether we come from mature or emerging nuclear programs, all of us can learn from each other. This conference provides an ideal venue for these learnings to occur. We thought deeply about the theme for the conference and the type of information that would be most useful to you. We designed the tracks with a specific logic in mind – we cover high level national strategies, the storage, transportation, recycling, and disposal of spent fuel; including understanding the impacts of advanced designs on spent fuel management; and have a session about how all of these impact each other. It is an exciting time for nuclear power. As of February this year, about 11% of the world’s electricity is generated by about 450 reactors. Since 2015, over 25 GW(e) have been added globally. Another 33 GW(e) are expected to be on line by 2020. Thirty countries have operational nuclear power plants. About 60 new reactors are under construction. Asia, especially China, has the newest construction; followed by Eastern Europe and Russia. In my country, the United States, nuclear energy provides over 55% of the carbon-free generating capacity. That results in a reduction of 528 million metric tons of CO2 per year! At this year’s International Congress on Advances in Nuclear Power Plants over 40 nuclear associations signed the Declaration of Clean Energy which called for a doubling of public expenditures on nuclear research and development. The intent is to allow nuclear energy to make it contribution towards carbon-free energy. Every nuclear power programme must manage spent fuel. The management of spent fuel will require commitments of resources spanning decades, possible spanning centuries. There will be many aspects of spent fuel management that must be addressed, both technical and nontechnical; including safety, security, economics, political, legal and regulatory, and societal. Maintaining a high level of operational excellence will be difficult over the long lifespan of a nuclear facility. Pressure to reduce costs can lead to unwise decisions. Personnel and organizational turnover can lead to lost knowledge. Complacency could grow over time. Facilities age and could become less reliable. New, unanticipated vulnerabilities could emerge over the years, such as cyber security. Nuclear systems are often perceived as controversial. Stakeholders are many, often have opposing views, and may be a source of conflict. The impact of stakeholders must be appreciated as they may influence policy and decision makers. Stakeholders generally want frequent engagement, transparency, and influence. The relationship between a nuclear facility and its stakeholders is important, and resources must be applied to support it. Collaborating with the public, stakeholders, and local governments increases the likelihood of success. An understanding of risk is critical to properly managing a nuclear programme. Even though accident frequency estimates are extremely low, consequences could be significant, costly, and long-lasting. The systems are complex and require credible science and sophisticated engineering to ensure risks are managed properly. Technically competent leadership in the government sponsor, regulatory agency, and implementing team is a major success factor. Leaders at all levels in an organization must embrace the behaviours that foster a strong nuclear safety culture. They must accept that there will be surprises, and plan for normal and abnormal events. They must understand uncertainty, risk, margin, defence-in-depth, and resiliency. Competent people are the most important success factor for a strong, safety culture. As Admiral H.G. Rickover, the father of nuclear safety in the USA, said, “Rules are not a substitute for rational thought.” There are many directions a nuclear programme could take. A country may choose an open fuel cycle and directly dispose of spent fuel. It may choose a closed fuel cycle and reprocess spent fuel. Or it may choose a hybrid model and do both. A county may implement fuel leasing where spent fuel is returned to the supplier residing in another country. A country may be a partner in an internationally shared disposal facility. For every possible direction a country could choose, there are lessons to be shared. Nuclear power systems are complex and integrated. We need to view these systems from the cradle to the grave. Nuclear power has over 17 000 reactor-years of experience! What a wealth of knowledge and expertise to help ensure nuclear power is safe and secure. Throughout the week will learn from this experience base and explore issues and successes, so we may apply these learnings and build a better future.
[en] This publication presents the proceedings of the IAEA International Conference on the Management of Spent Fuel from Nuclear Power Reactors, held in 2019, with the theme ‘Learning from the Past, Enabling the Future’. The purpose of the event was to provide a forum for the exchange of information on national spent fuel management strategies and on the ways in which a changing energy mix could influence these strategies and on how they support the achievement of national energy goals. The broad scope of the conference covered all stages of the management of spent fuel from the past, present and future technologies, and how it can be affected by the decisions taken in the rest of the nuclear fuel cycle. The event brought together experts from countries with decades of nuclear power operating experience and those from countries currently developing or considering a nuclear power programme. The importance of sharing data, operational experience, lessons learned and international collaboration in research and development (R&D) activities, and how its development and implementation can lead to attainable solutions was highlighted. Special attention was given to the young generation of professionals to support bridging the gap with the current ageing industry workforce.
[en] As Indonesia is planning to build an experimental power reactor of pebble bed HTGR type, it is important to determine the content of important fission product nuclides of its spent fuel. Identification the amount and type of the FPs is the first step toward the implementation of safeguards policy, management of the spent fuel and addressing the source term strength in case of an accident. The calculation was done using Monte Carlo method MCNP6 Code. It is intended to calculate the amount of nuclides that are important to safeguards, such as the remaining U-235 and the produced Pu-239; the amount of long-live minor actinides that are subject to spent fuel management; the amount of fission products that are important in addressing radioactive release in case of an accident. (author)
[en] During reactor operation, the mechanical properties of a nuclear fuel rod are radically altered. After discharge, alpha-decays and accumulated radiation damage or other processes associated to potential thermal variations occurring during interim storage, contribute to further ageing of the spent nuclear fuel (SNF). However, during all stages of the SNF man-agement (handling, retrieval, packing and transportation to final disposal or reprocessing) safety must be guaranteed. Assessment of the SNF mechanical stability against external stresses, which might be accidentally applied, requires representative reference data. Explicit tests simulating accidental conditions are conducted in the hot cells of JRC - Karls-ruhe, in the frame of a multi task collaborative research programme. Three-point bending and gravitational impact devices were developed and installed in the hot cells to investigate the SNF rods response under quasi-static or dynamic loads. Load-deflection curves are generated in the 3-point bending tests, whereas a high-speed camera records the rod rupture during impact tests. Results from investigations on LWR commercial fuel rods over an extended burn-up range are presented in this pa-per. SNF segments, pressurized at the original fuel rod pressure after discharge, were subjected to bending and impact tests. Similar masses, significantly less than a single fuel pellet, of fuel disperse upon pin rupture in both types of experiments. Only fuel fragments from the immediate vicinity of the rod fracture release. An image analysis methodology was developed to elaborate the sample’s behaviour under dynamic loads. Optical and electron microscopy were used to observe the mor-phology, orientation and population of the cladding hydrides, whereas the overall hydrogen concentration in the cladding was measured with hot extraction technique. Size distribution analysis on the released fuel particles was also performed. The study is augmented by modelling approach to evaluate the individual phenomena and parameters affecting the SNF properties. (author)